This invention is for a balanced valve with a sensor for moving the valve stem from one its valve open and closed positions to the other and powered actuator apparatus for moving the sensor in at least one axial direction.
U.S. Pat. No. 5,351,935 to Miyoshi discloses a control valve having a valve member resiliently urged to a closed position while a stepping motor has a threaded shaft that is axially movable by the rotation of a motor rotor. The downward movement of the shaft acting through a joint and a spring holder moves the valve member to a closed position.
U.S. Pat. No. 3,985,333 to Paulson discloses a balanced valve having a solenoid that, when energized, the valve stem is moved to an open position while a spring acts to close the valve.
In order to make improvements in valves with actuators for operating the valves between open and closed conditions, this invention has been made.
The embodiments of the valve device each include a valve body having an inlet and an outlet opening to an elongated bore extending axially through the body. A fitting has an axial bore opening to the body bore, extends within the body bore and is clamped between a bonnet and the valve body. Further, a valve seat is clamped between the fitting and the valve body axially intermediate the openings of the inlet and outlet to at least one of body bore and the fitting bore to have fluid in the body bore flow therethrough. A valve stem has opposite end portions axially slidable in the fitting and valve body bores respectively in close fit therewith with the opposite end portions being of the same diameters and a reduced diameter portion extending within the valve seat and between and joined to the opposite end portions. The actuator may be one of a motor driven device, a solenoid and pneumatic mechanism for applying pressurized fluid to the sensor.
One of the objects of this invention is to provide new and novel means for a valve to control fluid flow between the valve inlet and outlet. Another object of this invention is to provide a new and novel balanced valve that allows a low pressure force to open or close the valve and to reduce the load on the valve seat. A still further object of this invention is to provide a new and novel valve cartridge that may be operated by different types of actuation. A different object of this invention is to provide a new and novel balance valve wherein the inlet and outlet passages are reversible to permit bi-directional flow.